Object processing by conversion coating

Patent metadata

Field	Value
Publication number	US-2017342587-A1
Application number	US-201515534359-A
Country	US
Kind code	A1
Filing date	Dec 9, 2015
Priority date	Dec 17, 2014
Publication date	Nov 30, 2017
Grant date	—

Abstract

A method and apparatus for processing an object ( 4 ), for example an aluminium aircraft part, the method comprising: performing a first conversion coating process to dispose a first conversion coating ( 10 ) onto at least part of a surface of the object ( 4 ); partially masking the first conversion coating ( 10 ) disposed on the object ( 4 ); performing an etching process to remove, from the object ( 4 ), an unmasked portion of the first conversion coating ( 10 ) while retaining the masked portion of the first conversion coating ( 10 ) on the object ( 4 ); and performing a second conversion coating process to dispose a second conversion coating ( 12 ) onto a region of the surface of the object ( 4 ) from which the unmasked portion of the first conversion coating ( 10 ) was removed. A paint layer ( 14 ) may then be applied to, e.g., the second conversion coating ( 12 ).

First claim

1 . A method of processing an object, the method comprising:
performing a first conversion coating process to dispose a first conversion coating onto at least part of a surface of the object; partially masking the first conversion coating disposed on the object; performing an etching process to remove, from the object, an unmasked portion of the first conversion coating while retaining the masked portion of the first conversion coating on the object; and performing a second conversion coating process to dispose a second conversion coating onto a region of the surface of the object from which the unmasked portion of the first conversion coating was removed; wherein the first conversion coating process is a chromate conversion coating process, and the first conversion coating is a chromate conversion layer.

2 . A method according to claim 1 , the method further comprising applying a layer of paint onto either the second conversion coating or the portion of the first conversion coating retained on the object.

3 . A method according to claim 2 , wherein the layer of paint is applied onto the second conversion coating and not onto the portion of the first conversion coating retained on the object.

4 . A method according to claim 1 , the method further comprising, after the second conversion coating process, de-masking the object.

5 . A method according to claim 1 , wherein the first conversion coating process comprises disposing the first conversion coating onto the entirety of the surface of the object.

6 . A method according to claim 1 , wherein the second conversion coating process is an anodising process, and the second conversion coating is an anodic layer.

7 . A method according to claim 1 , wherein the object is at least part of an aircraft.

8 . A method according to claim 1 , wherein the first conversion coating defines an electrically conductive path through the coated object.

9 . A method according to claim 1 , wherein the first conversion coating process comprises:
exposing at least part of the object to a cleaning substance; rinsing the object to remove the cleaning substance from the object; exposing at least part of the object to a first conversion coating substance, thereby disposing the first conversion coating onto the at least part of a surface of the object; and rinsing the object to remove residual first conversion coating substance from the object.

10 . A method according to claim 1 , wherein the etching process comprises:
exposing at least part of the object to a cleaning substance; rinsing the object to remove the cleaning substance from the object; exposing at least part of the object to an etching substance, thereby removing, from the object, an unmasked portion of the first conversion coating; and rinsing the object to remove residual etching substance from the object.

11 . A method according to claim 1 , wherein the second conversion coating process comprises:
exposing at least part of the object to a cleaning substance; rinsing the object to remove the cleaning substance from the object; exposing at least part of the object to a second conversion coating substance, thereby disposing the second conversion coating onto the at least part of a surface of the object; and rinsing the object to remove residual second conversion coating substance from the object.

12 . A method according to claim 1 , wherein partially masking the first conversion coating disposed on the object comprises applying a vinyl tape onto part of the first conversion coating.

13 . Apparatus for processing an object, the apparatus comprising:
means for performing a first conversion coating process to dispose a first conversion coating onto at least part of a surface of the object; masking means for partially masking the first conversion coating disposed on the object; means for performing an etching process to remove, from the object, an unmasked portion of the first conversion coating while retaining the masked portion of the first conversion coating on the object; and means for performing a second conversion coating process to dispose a second conversion coating onto a region of the surface of the object from which the unmasked portion of the first conversion coating was removed; wherein the first conversion coating process is a chromate conversion coating process, and the first conversion coating is a chromate conversion layer.

14 . A coated object that has been processed using a method according to claim 1 , the coated object comprising:
a first conversion coating disposed onto a first region of a surface of an uncoated object, the first region being only part of a surface of an uncoated object; a second conversion coating disposed onto a second region of a surface of an uncoated object, the second region being different to the first region, second region being a region from which the first conversion coating has been removed; wherein the first conversion coating is a chromate conversion layer.

15 . An object according to claim 14 , the object being at least part of an aircraft.

Assignees

• Bae Systems Plc

Inventors

• Ashworth Sam Oliver
• Bowden Craig

Classifications

• C25D11/04

  of aluminium or alloys based thereon · CPC title

• C25D11/38

  Chromatising · CPC title

• C23C22/83

  Chemical after-treatment · CPC title

• C25D11/08

  containing inorganic acids · CPC title

• C25D11/02

  Anodisation · CPC title